#include <stdio.h>
#include <stdlib.h>
int main(int argc, char const *argv[]) {
    int sum, i;
    for (i = 1; i <= 100; i++) {
        sum += i;
    }
    printf("1+2+3+..+100 = %d\n", sum);

    int a = 10, b = 20;

    return 0;
}
